US Government As Represented by the Secretary of the Army

William C Pittman

Paul R Ashley

Ralph H Halladay

S Richard F Sims

Walter E Miller, Jr

Michael Scalora

Mark J Bloemer

Jonathan P Dowling

Charles M Bowden

Michael R Christian

Richard A Lane

S Richard Sims

Susan D Terrill

James H Mullins

Richard G Westrich

James E English

John B Meadows

John C Fleischman

Raymond C Bates

Huey F Anderson

An image analysis and enhancement system is provided with an image processor, imaging metrics, an image storage depository, and a reconfigurable sensor device that can be present at the same location. A remote reconfigurable sensor device is connected to the image processor via a communication link. Both the reconfigurable sensor device and the remote reconfigurable sensor device are equipped with selectable optical elements and imaging elements that are selected in a desired combination and orientation to capture desired image frames from a target scene or object. The selectable optical and imaging elements are provided with actuating devices to move and translate the selected optical and imaging elements into a desired orientation with one another, so that a desired imaging technique can be employed to obtain an enhanced image. The system is applicable to industrial, medical and military use.

Reconfigurable imaging system

Image analysis and enhancement system

Parametric processing capability is added to a typical sensor so that a target object can be more clearly distinguished from the background clutter in a given scenery. A polarizer with several segments of different polarization orientations is used to improve the typical sensor. The segments are sequentially advanced to pass therethrough infrared radiation images of pre-selected polarization orientations which are then collected by respective polarized frame grabbers. Image processing circuit processes these images to yield the polarization difference between any given pair of orthogonal polarizations. In a surveillance network, the polarization differences are subsequently used in the control center, to which such sensors are connected, to enhance the distinction of the observed objects against the background clutter suspended in the propagation medium.

Sensor having differential polarization and a network comprised of several such sensors

Applicants' ATR system is weather-agile because it is comprised of a primary target sensing means that is capable of surveilling the target scene in foul or fair weather, and a secondary target sensing means that is also capable of sensing targets in various weather. The primary and secondary sensing means communicate through a control center so that ultimately, among several weapons available, the most strategically located and equipped weapon is activated for the destruction of a selected target, given the weather. The control center accomplishes the communication by receiving the sensed target signature from the primary sensing means, processing the signature using database already resident in the center and transmitting the processed target signature to the weapon possessing the greatest potential for successfully destroying the target.

Weather-agile reconfigurable automatic target recognition system

An improvement in a semi-active laser last pulse logic missile seeker is disclosed and claimed. In one embodiment, the improvement includes a first polarizer disposed in the detection field of view of the PIN photodiode detector and a second polarizer disposed in the detection field of view of the staring imaging infrared focal plane array. Each of the first and second polarizers has an identically configured plurality of segments. Each segment allows transmission of a different polarization than other segments and is sized to completely cover the fields of view of both the PIN photodiode detector and the staring imaging infrared focal plane array. First and second actuators are connected to the first and second polarizers, respectively, to synchronously and simultaneously step identical and corresponding segments in a plurality of discrete steps within the fields of view in response to incoming temporal and spatial laser returns.

Polarized semi-active laser last pulse logic seeker using a staring focal plane array

The photonic band gap (PBG) dual-spectrum sensor utilizes the frequency-selective properties of a photonic band gap device constructed in accordance with this invention to separate incident electromagnetic wave into two frequency bands. The parameters of the PBG device are chosen so that one frequency band is transmitted through the device with low attenuation while the second band is reflected with low attenuation from the front face of the device. This separation of the two frequency bands allows separate detection processes to be performed to recover the information content of the two signals before the information is fused in subsequent signal processing operation. Such a PBG device would be useful in missile seekers that seek to distinguish a target object from its background.

Photonic band gap dual-spectrum sensor

The Multispectral-Hyperspectral Sensing System (MHSS) comprises a control center, a surveillance platform and at least one weapon battery with known sensing and destroying capabilities. The control center has access to pre-existing information relating to the target scene and potential targets, although not necessarily current, as well as the capabilities and limitations of the available weapons. This pre-existing information is communicated to the surveillance platform to be used in collecting hyperspectral/multispectral image data of the target scenery and to derive from the collected image data the relevant current target data subset. The derived data subset is then down-linked to the control center, which performs further processing to make it useful to the selected weapon. The weapon receives the target signature update from the control center and, in response, performs a significantly more precise strike at the selected target than based just on the a priori knowledge base.

Multispectral-hyperspectral sensing system

The millimeter-wave zoom antenna for guiding a beamrider hypervelocity missile uses varying range information derived from the flight of the missile toward the target as control signals for the beam control computer to perform electronically the zooming and the nutation of the millimeter wave guidance beam that emits from a phased array antenna so as to maintain a constant energy density at the missile receiver regardless of the actual distance of the missile from the launch platform at any given time.

Millimeter-wave zoom antenna for guilding beamrider hypervelocity missile

The polarization-resolving infrared imager employs the configurations of either first-generation (60 horizontal rows by 1 vertical column of detector elements (pixels)) or second-generation (at least 240 horizontal rows by 4 vertical columns of detector elements (pixels)) infrared imaging detector devices and polarization filters that work in conjunction with the infrared imaging detector devices to separate incoming infrared radiation into portions each having a different polarization orientation. Such polarization separation enables the production of visible images in which various aspects of the scene are differentiated. In the preferred embodiment using the second-generation infrared imaging detector device, polarization-filtering grids are integrated onto the detector. The detector elements in three of the four columns have coupled thereto polarization filtering elements to filter, respectively, horizontal, vertical and 45-degree polarizations of the incoming infrared radiation. Using a scan mirror of sufficient sweep in conjunction with the detector device and the polarization-filtering grid results in one frame of the scene with horizontal polarization, one frame with vertical polarization, one frame with 45-degree polarization and a frame with no polarization distinction, all with one sweep of the scan mirror in real-time scenario. This provides nearly simultaneous infrared scenes at different polarizations from a single cycle of the scan mirror.

Polarization-resolving infrared imager

A space-fed phased array radar utilizes a network of improved Mach-Zehnder nterferometers to provide a space-fed, optically controlled millimeter wave/microwave antenna array that is capable of either one-way or two-way transmission. In the two-way communication relay mode, both ends of the relay link can remotely switch from a transmit to a receive mode and vice versa while, at the same time, steering the outgoing radiation beams on both sides of the relay so as to achieve maximum signal-to-noise ratio between the two terminals (i.e. signal stations) of the communication link. The improvements include receiving antenna with beam-scanning capability to receive millimeter or microwave signals from a first signal station, amplifiers to amplify outgoing signals prior to being radiated outwardly by transmitting antenna and a means to render the same antenna array capable of being used in a two-way transmit and receive mode. Controlling in a prescribed manner the voltage or current that is applied to the optical signal determines the shape and direction of the outgoing signal radiated into space.

Communication relay and a space-fed phased array radar, both utilizing

Synthetic discriminant function automatic target recognition system augmented by LADAR combines, through the synthetic discriminant function (SDF), the active LADAR data of the potential target object with the passive infrared imagery of the target and background. In doing so, the system not only recognizes and classifies the target but also provides the range profile of the target object by analyzing the amplitude of the reflected return signal when appropriate. The live target scene imagery in passive infrared is detected, filtered and subsequently complex multiplied with pre-existing synthetic discriminant function to produce a two-dimensional cross-correlated surface. Analogous process is performed on the active LADAR range and intensity images of the live target scene with corresponding pre-existing synthetic discriminant function for the same target pose and scale as in the passive infrared correlation step. Ultimately, the target information thus acquired in passive infrared and active LADAR is fused to obtain a more accurate determination of the target location and classification than is possible using either infrared or LADAR alone.

Synthetic discriminant function automatic target recognition system

The single channel transceiver with polarization diversity is a target detion and tracking system that results from combining the well-established technology of single channel transceiver with that of microstrip polarization-diverse antenna. The single channel transceiver with polarization diversity transmits a pair of pulses of a pre-selected polarization sense toward a target object and receives two scattered pulses of orthogonal polarizations in rapid sequence. Thereupon, a second pair of pulses, this time of opposite polarization, is transmitted and, again, two scattered pulses of orthogonal polarizations from this second pair of transmitted pulses are received in rapid sequence. Thus, the single channel transceiver with polarization diversity has the capability to obtain the complete scattering matrix of a target by use of four transmitted pulses. The received scattered pulses are further processed by the transceiver to derive the polarization signature that is indicative of the nature of the object from which they scattered in reflection and thereafter used to identify the target among clutter or background.

Single channel transceiver with polarization diversity

The dual band millimeter-infrared fiber optics guidance data link presents nhanced seekers with the capability to see through cloud cover while exhibiting resolution that is adequate to strike high value targets. Such a seeker may use a bi-directional dual band data link in the form of a secure, high bandwidth optical fiber between the missile in flight and the ground station, offering the capability to transmit millimeter-infrared sensor data from the missile to the ground station and transmit missile guidance signals from the ground station to the missile over the same high bandwidth optical fiber. Both infrared and millimeter target signature data is made available in the ground station by the use of applicants' invention. Such availability not only provides the gunner with an additional capability to identify the target and thus avoid fratricide, but fusion of the infrared and millimeter data in the automatic target recognizer in the ground station provides an additional capability to classify and identify targets while preserving high-value components of the data link by their removal from the missile to the ground station.

Dual band millimeter-infrared fiber optics guidance data link

This invention is a beam rider system and method that utilizes polarization-agile millimeter beams. Information is spatially encoded in the beams by varying the rate of rotation of the linearly polarized vector of the beams. In one embodiment, information is encoded on a beam that is nutated around a centerline flight path of a missile. In another embodiment, information is encoded on four parallel beams that form a centerline which is the intended flight path of the missile. Receiver means in the flying missile receive and decode information from the beams and use this decoded information to guide the missile to a target.

Missile beamrider guidance using polarization-agile beams

Van Atta array is used to receive a millimeter wave beam from a beam transmitter located in a missile in flight and retransmit the beam back to its source along its original optical path after the beam is phase conjugated and modulated at a tracking station by imparting to it missile guidance information. The missile extracts guidance information from the retransmitted beam and guides its trajectory closer to the course leading to the target.

Growing community of inventors

Huntsville, AL, United States of America

William C Pittman